Stone ceiling



web. 2,-1-1943. l (E. GW'R r2,309,842

Y 'STONE CEILINGS Filed Feb. 7, 1939 2 Sheets-SheetZ Patented Feb. 2,1943 STONE CEILING Engelbert Grwer, Leipzig, Germany, assigner toIgnacio Arane'ta, Lima, Peru Application February 7, 1939, Serial No.'255,061 'In Germany ApriLZlO, 1937 3 Claims.

This invention relates to fhollow .stone ceilings built withoutboardings, and more particularly tohollowstone ceilings and methods ofbuilding the same utilizing yauxiliary iron girders 'for the support ofthe ceiling stones during construction of the ceiling.

It is an object of this invention to provide ceiling stones which, when.being suspended from an auxiliary iron girder, take vand :maintain astrictly horizontal position;

It Sis another object of this invention to provide auxiliary irongirders vfrom which the ceiling :stones are suspended in strictlyhorizontal position, which are .highly resistant to bending or torsionalstresses, which lend themselves to Aready adaptation to varying widthsand loads of the ceiling, and which can be used in connection withadditional lauxiliary supporting structures.

Other objects, and the manner in which the same are attained, willappear from the following description.

Inrthe prior art, reinforced hollow stone ceilings were ordinarilyconstructed with the aid of a Wooden lboarding supporting the ceiling.from below during the setting of the concrete mortar and simultaneouslyinsuring the ceiling of -a plane surface. Attempts have also 4been lmadeto build lceilings of the aforenoted type without `the assistance of asupporting wooden-boarding,

lbyrusing auxiliary iron girders supporting the individual stones inrows. Prior to the present invention, however, the relimination ofwooden boardings and the substitution` therefor or auX- 4iliary girdersresulted in anumb'er 'of drawbacks which rendered this method more orless impractical. For example, the ceiling stone when suspended from theauxiliary girders would not take Va strictly horizontal position, -as isrequired in order `to obtain a planeceiling. .Moreoven the auxiliarygirders were exposed `to deterioration iby lall Vsortsof bending andtorsional stresses and frequently proved even inoperable where the width`and .loads of the ceiling deviated somewhat from the more customarystandards.

The present invention contemplates the elimination of the drawbacksexemplied above, and

.the construction of a hollow stone ceiling with Athe aid of auxiliaryiron girders, `by arranging on the stones projections and recessescooperating-so as to engage part of the girder in a'mannersuch that byvirtueof this controlled engagement,'the stones are positively caused to`'take and maintain. a strictly horizontal position. Therinvention.further contemplates the vprovision of auxliliafry..girders having suchshapes Sas ltoren'der them highly resistive to bending and torsionalstresses, to vpe-rmit 4their combination in partly nested form .toinsureoptional extension, and the Aprovisionol `auxiliary supportingstructures for use in connection With the auxiliary girders und'ercertain speciedconditions.

11n the drawings a'ixed to this speci'lcation and for-ming part thereofseveral embodiments of this finventionrare illustrated diagrammaticallybyway of example.

In the drawings,

.Figure `1 is a perspective view-of one form of a stone ceilingaccording 'to the invention in the process `ol being assembled,

v Figure 2 .is a perspective view of a detail of Figure 1,

Figure 3 illustrates a cross-section taken along line III-III of yFigurel,

Figure 4 is va, cross-section taken along line IIV-IV in Figure 3,

Figure?) illustrates a hollowstone accord-ing to the 'invention as shownin Figures l `to 4, drawn to a larger rscale,

lFigures 16, f7 .and -8 .show .modified forms of a fhollow stoneaccording to the invention;

Figures 19 .and V1'() illustrate auxiliary girders .employed inlne'stedicondition in connection with lthe stones according v'to Figures5 and 6, respectively;

Figures llan-d .12 illustrate modied forms of the :auxiliary girderslikewisein nested condition; .and

AFigur-es v13, .14 and 15 show various embodilments of additionalsupporting structures to be .usedin connection with the Iauxiliarygirders.

. IReferring :now to the drawings, and rst to EEigures l itol, the wallsI :support two Vbed stones 12, which preferably are .ordinary ceilingstones, and which in turn support-an .auxiliary girder 3,preferably-made l'of iron. rEhe girders 3 are pro- 'vided with a :flangef4 adapted 4to Vengage a re- :cess 5 protected @by a tongue-shapedprojection '6 :arranged Ain 'or 'on theitop part of 'the `ceiling stonesIgener'ally indicated at .1. The joints intermediate the ceiling stonesarenlled with morftarlas -indicated vat 8, reinforcing irons 9 'beinginserted in the mortar so as to be completely enclosed thereby.

Inthe construction @of the ceiling, two ceiling stones-2 are put -onopposite walls and an auxiliary girder `3y-lis -put on top of these bedstones solas 'to engage with its ypart Y'2l the recess v". providedtherein. -Now-ithe ceiling stones 'l are suspended individually from`the auxiliary Vg-irder 3, Iby engagement of their recess l5 asprotected by the projection 6 with the girder part 4, while insertingmortar so that the longitudinally extending joint to the rear of thestones and likewise the joints intermediate any two stones arecompletely filled with mortar, as indicated at 8. Hereafter the front ofthe entire stone row is supplied with a mortar bed consisting, e. g., ofstiff concretemortar mixedin the proportion 1:3 and in this mortar bedthere is inserted the reinforcing iron 9 having the statically requiredstrength so as to be completely enclosed by the mortar. Now a secondauxiliary girder is laid on Figure 7 indicating this arrangement withrespect to the structure shown in Figure while Figure 8 shows a similarmodification of the structure indicated at Figure 6.

The auxiliary girder from which the stone are to be suspended mustanswer manifold requirements. It must be of light weight and easy tohandle and it must be adapted for causing the stones to take a strictlyhorizontal position once they are suspended therefrom. The auxiliarygirder further must possess high resistance to bending stresses so asnot to be pulled downtwo additional bed stones put on the walls and Lthe suspension of ceiling stones from this second is built up andreinforced until the entire ceiling is completed. This operation ispreferably performed by a brick-layer standing on a displaceablescaffold as indicated at I0 in Figure 1.

With ceilings of this type it is of prime importance that the ceilingstones, when suspended from the auxiliary girder, take and maintain astrictly horizontal position. For this reason, the ceiling stone must beprovided for a particuluar engagement with the girder such as to insureits taking and maintaining a horizontal position, and Figure 5, showingthe arrangement of the preceding figures however drawn to a largerscale, indicates one structural arrangement for this purpose. In thisembodiment of the invention, the stone 'I is formed with a wedge-like orconical recess 5 protected by a similarly shaped tongue or projection 6,said recess and said projection being so arranged with respect to thegirder portion 4 from which the stone is suspended, that the pointofsuspension, indicated at Il, is located at some distance from thevertical of gravity indicated at l2. This asymmetric arrangement createsa tilting Vmoment in the stone acting in the direction 0f the arrow I3and producing a horizontal clamping effect which causes the stone to bepressed onto the portion i of the auxiliary girder 3. this portion 4extends in strictly horizontal direction, the stone of necessity musttake and maintain a corresponding, strictly horizontal position.

As shown in Figure 6, the stone portion adapted for engagement with theportion 4 of the girder 3 may also be formed by a recess such asindicated at I4, a rectangular projection I5 and a ledge-shaped portionI6, the latter two delimiting the recess on opposite sides thereof. Thevertical distance intermediate the bottom surface of the projection I5and the top surface of the ledge i6 is equal to the thickness of thebottom portion 4 of the girder 3, and the horizontal distance betweenthe near edges ofthe projection I5 and the ledge I6 is providedsufficiently large for permitting the stone of being slipped on theportion 4 of the girder by a small rotary movement. The ledge I6 issufficiently close to the opposite wall l1 of the recess so as to permitof support of the portion 4 on the ledge even when the portion 4 extendsfully into the recess lil. With this arrangement likewise is the pointof suspension arranged outsideof the axis of gravity l2 and thereforeresults likewise in a positive, strictly horizontal guidanceof thestone.

As shown in Figures 7 and 8, it is by no means necessary to provide thegirder engaging portion in a recess of the stone, and it is equallypossible to arrange thisstructure on ,top .Of the stone, i'

Since wardly by the ceiling in case heavy stones are employed. Theauxiliary girder further must possess as high as possible a resistanceto torsional stresses, since the load applies on the outer edge of thebottom portion of the girder so as to tend to twist the girder near thecenter thereof. It is further desirable that the girders may be nestedto permit of using a combination of several auxiliary girders wheneverthe width of the ceiling extends the permissible length of a singlegirder. This nesting is particularly irnportant in a case where aceiling is to be constructed between two already existing walls andwhere the girders would have to be cut to size unless two similargirders can be nested so that their total length corresponds exactly tothe desired width of the ceiling. Finally, with very considerable widthsof the ceiling it is desirable to employ the auxiliary girders invconnection With additional auxiliary supports.

The manifold requirements enumerated above are answered by the auxiliarygirders according to the invention.

As best seen in Figures 9 and 10 the `auxiliary girder also shown in thepreceding figures comprises a straight center portion 20, and top andbottom flanges 2| and 22 extending in opposite directions at rightangles to the center portion. Figure 9 illustrates two such girders innested condition in engagement with a stone according to Figure 5,whereas Figure 10 is a similar showing of the same girder, also innested condition, in engagement with a stone according to Figure 6. y

Instead of comprising a vertical center portionv and two flangesextending at right angles thereto, the auxiliary girder also may takethe shapes indicated in Figures 11 and 12, with a somewhat slopingcenter portion 23 and top and bottom flanges V24 and 25l extending inopposite directions and strictly horizontally, these shapes resemblingZor S shapes. It is noted that here again two girders are shown in theirnested, i. e., partly overlapping condition.' Y

The auxiliary girders according to the invention preferably are made' ofstrong sheet iron, of a thickness in the neighborhood of, e. g., 4 mm.,soV as to be of considerably lighter weight than the customary girdersand prole irons having the same resistivity. Accordingly, the auxiliarygirders according to the invention are much more readily handled thanare the heavier girders now on the market. The high center portion andthe two flanges render the auxiliary girds highly resistant to` bendingand torsional stresses so that frequently one of these girders aloneWill be suflicient to bridge even comparatively large Widths. In a casewhere the length of one auxiliary girder is not sufficient, two suchgirders can be used, as shown'in the drawings. Since it is possible tonest the lauxiliary girders in the manner shown, itis possible toprovide in the center of the'width` to be 'covered' Aa-ternporary thirdsupport by means of an auxiliary support on which a ceiling stone islaid which in turn supports the overlapping portions of the twoauxiliary girders. In the same manner it is possible to provide a fourthtemporary support and t subdivide the width into three portions, as maybe required in a case where, e. g., a very strong pressure concrete isto be appliedto the ceiling.

As seen in Figure 9, the conical shapes of the projection and recessportion on the stone are eminently suitable for these auxiliary girders,as they permit of ready engagement even With the double thickness of theflanges as caused by the over-lapping thereof. However, as seen inFigure 10, the stone according to Figure 6 likewise may readily be usedin connection with overlapping, nested auxiliary girders, since at thepoints where the girders over-lap a brick-layer must merely remove, by asingle blow of his hammer, the small stone ledge so as to create spacefor the double thickness of the flanges.

With respect to the Z or S-shaped auxiliary girders shown in Figures 11or 12, it is noted that these profiles are particularly advantageous inthat the rounded back of these girders enables the same to be readilydriven out after the setting of the mortar in the joints of the stones;moreover these auxiliary girders are so constructed that when theyover-lap they lie particularly closely together. Furthermore, thesegirders may be used in any position without an angular displacementabout 180 being necessary. The bent flanges 24 and 25 increase theresistance of the auxiliary girder to torsional stresses. Finally, thebends of the flanges 24 and 25 permit of ready insertion of a woodenwedge for holding the girder in position, which is prevented fromescaping sidewardly by the bent flanges.

Where the ceiling is very high above the floor, it is not alwayspossible to employ such scaiolding as indicated in Figure 1. Moreover,it is frequently desired to keep the space below the newly constructedceiling perfectly free from any auxiliary scaifolding. In cases of thischaracter additional supporting structures comprising one or severalauxiliary girders of suflicient resistivity may be used, in connectionwith the auxiliary girders mentioned above, which are suspended fromthese additional supports and fixed thereon r by means of an ironconnecting piece engaging the upper ange of the auxiliary girder.

As shown in Figures 13 and 14, the auxiliary girder 30 may be mounted ina connecting piece or lamella 3| which in turn is supported on anadditional auxiliary girder 32, which as shown, may display an I-prole.A wedge 33 is preferably provided for forcing the upper flange of theauxiliary girder B in contact with the additional auxiliary girder 32.It is obvious that, if the connecting piece or lamella is provided of asomewhat greater width, several I-proles may be used; likewise it isevident that various other proles, including rails, may be employed.

As indicated in Figure 15, the auxiliary girder 30 may also be suspendedfrom a connecting piece or lamella 3| which extends in the spaceintermediate two U-shaped profiles 32a, 32h, a Wedge 33 securing contactof the auxiliary girder 30 with the U-shaped additional auxiliarygirders 32a, 32h. In a similar manner, the auxiliary girder may besecured to various other additional auxiliary supports.

Ordinarily, the auxiliary girder is supported by the bed stones instrictly horizontal position, owing to its weight and the engagement cfits bottom ilange with the recesses provided in the bed stones. If it isdesired to more rmly secure the auxiliary girder on the bed stones, awedge, preferably of wood, may be inserted next to the bottom ange ofthe auxiliary girder in the recess of the bed stone so that the uppersurface of th-e wedge abuts against the top iiangeof the auxiliarygirder which thus gains additional importance for this purpose.

For the same purpose of securing the auxiliary girders in strictlyhorizontal position, an additional auxiliary support such as shown inFigures 13, 14 and 15 may be employed which may consist of thin profileiron as, in this case, it must not carry any weight, but solely servethe purpose of maintaining the auxiliary girders in strictly horizontalposition and to inter-connect :and intersecure the various auxiliarygirders. The auxiliary girders according to the invention thus proveadvantageous also with respect to the task of securing them in strictlyhorizontal position to obtain a plane ceiling.

Wherever desired the ceiling stones according to the invention may beprovided with suitably arranged stone ledges in order to facilitate theapplication of mortar and to increase the static Values of the stones.

I wish it to be understood that I do not desire to be limited to thedetails of construction or design las shown or described, as numerousmodifications within the scope of the appended claims will be obvious toany person skilled in the art.

I claim:

l. A ceiling stone for use in a ceiling produced with the aid ofremovable auxiliary girders including bottom flanges, comprising awedgelshaped projection and a similarly shaped recess formed thereby,for suspending the stone from a bottom flange on one of said girders,said projection and said recess being arranged so that the point ofsuspension is located outside of the axis of gravity of the stone, solas to produce a tilting moment securing the stone firmly on the girderin a strictly horizontal position.

2. A ceiling stone for use in a ceiling produced with the aid ofremovable auxiliary girders including bottom flanges, comprising arecess portion, a rectangular projection partly covering said portionand a ledge portion adjoining said recess portion, said recess portionbeing adapted to engage a bottom flange on one of said girders so thatit abuts against said projection and said ledge portion, the verticaldistance between the projection and the ledge being equal to thethickness of the said ilange and the horizontal distance between theprojection and the ledge being sufficient for permitting ready insertionof the flange into said recess, whereby the stone is secured on saidflange in a strictly horizontal position.

3. The method of producing stone ceilings which comprises suspending thestones by their tops with their bottom faces extending freely in acommon horizontal plane inserting in the interstices between the stonesmortar and reinforcing means and, after the mortar has set, severing theconnection between the stones and the points from which they aresuspended.

ENGELBERT GRWER.

